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engine starting issues after rebuilt

yes, i bought an oil primer shaft that you insert in the distributor hole, and attached it to a drill, and i spun did it until i saw oil coming out of the pushrods
is there a specific tool to get the springs with the heads on ? how do you not get the valves to drop in the cylinder ?
 
Yes, there are several but I'm at work and can't elaborate at the moment
Maybe someone else will jump in before I can.
 
Yep, looks almost like a pry bar, forked on the end with a hole for the stud.
When you bring the cylinder to TDC with the plug in, the air left in the cylinder should hold the valve up. Always has for me any way.

You back the nut off, pull the rocker, reinstall the tool and nut, and pull. Usually the keeps come right out. Loosen the nut and pull the spring. Reverse process to reassemble
 
I've seen a length of 3/8" poly rope pushed through the spark plug hole, then rotate up to TDC to keep the valves near the seat...
 
The rope trick or compressed air with an adapter fitting into the cylinder one at a time.
Turn the engine until both valves are closed and the piston is at the bottom so it doesn't rotate down with the air pressure.
Apply 90 psi to hold the valves up and use a valve spring compressor that grabs the spring itself and compresses it or a lever type will work.
Works great as long as you don't lose air pressure.
You can rent the spring compressor from an auto parts store. A compression tester should have the right fitting to hook up to an air hose.
I've used the comp air method but not the rope method but both work.

The rope jams between the piston and valves to hold them up, probably simpler.​
 
the rope thing sounds more simple, plus I don't have an air compressor. So you basically insert the rope in the sparkplug hole, and put the piston in TDC so that the valve sits on the rope, that will be held by the piston top ?
 
bent72 said:
yes
Click to expand...

got it.

So, here is a video of the startup. I removed the valve covers, and all the rockers seem to move correctly, all the way up, and all the way down. However, we can here a "pop" or "tac" noise, on the driver's side. Would that be an exhaust leak ? or the timing that would make the "pop" from the carb ? or a bad valve adjustement ?


I also will need to adjust the idle
 
Well lets eliminate valve adjustments before we look for anything else.
What/how are you doing to adjust the valves running? Is there a vacuum gauge involved?
 
bent72 said:
Well lets eliminate valve adjustments before we look for anything else.
What/how are you doing to adjust the valves running? Is there a vacuum gauge involved?
Click to expand...

No i adjust the valves engine OFF, I start with the first cylinder of the firing order (#1) and i put the intake valve fully opened, and I adjust the intake valve of opposite cylinder of firing order (#6) which technically should be at the exact position of a close intake valve. I tighten it until there's no play between rocker arm and pushrod, and once play is gone, i tighten it half a turn.
and I go to the next cylinder, Intake valve of #8 fully open, adjust intake valve of #5 etc... and then i do the exact same thing for the exhaust valves.

I don't have a vacuum gauge, and to be honest, all the vacuum thing has always been quite confusing to me... :(
 
should I adjust them engine ON, and bolt each of them until there's not more "tic tic tic" ? it gets pretty messy quickly though...
 
Either way works. If you adjust them not running, you should not have click at the valve on fire up. If so, they are loose.

The advantage of the vac gauge is it tells you strength of the signal for anything you touch, and shows you when the motor has fully recovered after the valve adjustment.

Running i back then off until they click. Then very slowly tighten 1/4 turn. Allow the motor to recover and add another 1/4 turn slowly. Dependent on the manufacturer, but usually add another 1/4 turn after the vacuum returns. Go slow all the way around. They make little tabs that snap on the rocker to help keep the oil from flying.
 
bent72 said:
Either way works. If you adjust them not running, you should not have click at the valve on fire up. If so, they are loose.

The advantage of the vac gauge is it tells you strength of the signal for anything you touch, and shows you when the motor has fully recovered after the valve adjustment.

Running i back then off until they click. Then very slowly tighten 1/4 turn. Allow the motor to recover and add another 1/4 turn slowly. Dependent on the manufacturer, but usually add another 1/4 turn after the vacuum returns. Go slow all the way around. They make little tabs that snap on the rocker to help keep the oil from flying.
Click to expand...

would that really healp the oil from splashing ? I tried to do it engine ON once, and it was a real mess. Since I don't have a vacuum gauge, how long do you usually wait between the 1st and the 2nd 1/4 turn ?
So that "pop" misfire/exhaust leak noise we hear in the video could be a valve that is too tight, and is still open when it fires, and make fire blows through the carb ?
 
1) yes
2) depends on the motor, but you can hear the motor recover. Wait another 5 seconds after you hear it recover.
3) yes, could still be a valve issue.
 
thanks for these infos. Will work on it as soon as I have time
 
concerning the oil, should i still put some new break in oil + additive for the next 50 miles ? or regular oil is good now ?
 
I only every ran break in oil if the entire motor was new. That said after any major internal change, i used to run it 500 miles and drop it.
 
Philouw said:
got it.

So, here is a video of the startup. I removed the valve covers, and all the rockers seem to move correctly, all the way up, and all the way down. However, we can here a "pop" or "tac" noise, on the driver's side. Would that be an exhaust leak ? or the timing that would make the "pop" from the carb ? or a bad valve adjustement ?


I also will need to adjust the idle
Click to expand...

Sounds like an exhaust leak at the manifolds in the video,but its hard to tell ,the audio can make one thing sound like another..it idles pretty smooth for the valves to be far out of adjustment..

I like adjusting the valves "by the book",it tells you to set the engine up on #1 tdc,and gives you the sequence of which valves on what cylinders can be adjusted,then you set it on #6 tdc and adjust the rest,by turning the push rods with your fingers as you slowly tighten down the rocker arm nut--just as it gets to where you cant spin the push rod,you go another full turn (or whatever spec the cam instructions say if its an aftermarket one)...
Once you get used to adjusting them that way,you can just set them and put the rocker covers on and not have to mess with them again..
It also prevents cam lobe damage from starting it with the valves set too loose,and the possibility of tightening the rocker arm nut down too fast,which could bend a pushrod or a valve..not to mention the mess,with oil flinging everywhere..V8 chevy valve adjustment.jpg
 
diesel4me said:
Sounds like an exhaust leak at the manifolds in the video,but its hard to tell ,the audio can make one thing sound like another..it idles pretty smooth for the valves to be far out of adjustment..

I like adjusting the valves "by the book",it tells you to set the engine up on #1 tdc,and gives you the sequence of which valves on what cylinders can be adjusted,then you set it on #6 tdc and adjust the rest,by turning the push rods with your fingers as you slowly tighten down the rocker arm nut--just as it gets to where you cant spin the push rod,you go another full turn (or whatever spec the cam instructions say if its an aftermarket one)...
Once you get used to adjusting them that way,you can just set them and put the rocker covers on and not have to mess with them again..
It also prevents cam lobe damage from starting it with the valves set too loose,and the possibility of tightening the rocker arm nut down too fast,which could bend a pushrod or a valve..not to mention the mess,with oil flinging everywhere..View attachment 190414
Click to expand...

Yes I've seen this method too, and the one that says to rotate the engine until both valves are close, and set the valves on the same cylinder, I'm pretty sure they both work, but in my opinion, what I understood, is that, to be adjusted, the valve (or more precisely, the lifter) has to be on the lowest spot of the lobe (the heal i think), which should be at the exact opposite of the "peak" of the lobe, but it's hard to know exactly where the lifter sits on the lobe. So the most accurate way is to put one valve on that lobe's peak (valve fully open) and set the opposite valve (of the firing order), since it's the opposite valve, is should be at the exact point opposite of the lobe's peak. If that makes sense. It is way longer than the 2 other methods, but it seems more accurate. They explain it very well in here :

http://www.centuryperformance.com/valve-adjustment-procedure.html

The only thing is that, it is advised to do it when engine is warm, I guess it has something to do with the oil being more fluid
 
Theres a handful of ways. Running or the method Diesel listed are the two i recommend unless i am there to show what im doing. Either way, take deep breath and carry on.
 
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